Spark-plug.



W, T, M. BESSON.

SPARK PLG.

AE'PLITION EILEB DEC. l5.

wia.

Patente Dec. 1914 'UNITED STATES rArENT OFFICE.

WILLIAM T. M. Basson, or sELMA, ALABAMA, AssfGNon or ONE-HALF To H. A.

VAUGHAN, or snLMA,

SPARK-HUG.

Specification of Letters Patent.

Patented Dec. 1, 1914.

Application led December 15, 1913. Serial N o. 806,936.

To all whom t may concern:

Be it known that I, WILLIAM T. M. BES- soN, a citizen of the United States, residing at Selma, in the county of Dallas and State of Alabama., have invented certain new and useful f Improvements in Spark-Plugs, of which the following is a specication.

This invention relates to spark plugs, and an object of the invention is to provide a spark plug so formed as to prevent the interference with thespark by thel accumulation of oil on the electrodes.

4A further object of the invention is to provide the active portion of the spark plug 1n a continuous surface so that the oil which collects thereon may drip from the bottom of the plug, and not remain in any objectionable quantities on theI active portions of the plug.

With these and other objects in view, the invention consists in certainconstructions, combinations and arrangements of the parts as will be hereinafter fully described and claimed.

The accompanying drawing shows a vertical central plug.

The general aim of the present invention is to provide a spark plug the depending portion of which lsprovided with a smooth surface which terminates in a conical point so that oil accumulating upon the surface will drip from the point. The points between which the spark jum s, are removed somewhat fromnthe point o the plug.

Referring more particularly to the drawings, it will be seen that the hollow threaded tube 1 which is threaded into the walls of the engine cylinder, has the lower end thereof pointed in the shape of a cone as at 2. The insulating material 3 is shaped so as to conform to the interior of the tube 1, and has a conical point so that the surface between the vanishlng edge 4 ofthe conical point 2 of the threaded tube, lies against the conical surface 5 of the insulating material. It will be understood of course that the grounded side o f the -ignitionsystem will be connected to the tube -1. The other side of the ignition system comprises a wire 6, the point of which is conical as shown at 7, the point 7 vanishing aE at 8.

` It will be understood from the drawing section taken through the spark' that the surface between the conical end 2 of the threaded tube, jthe conical surface of the insulating material, and the conical surface of the point 7, forms altogether substantially a conical surfacesmooth in contour so that oil may run from the grounded elecutrede to the insulating material, and from there on to the larger point of the conical point 7 from where it will go to the point 8 and drop ofi' `intothe cylinder. It will be seen that `the ,desirable feature is that the v surface formed by the exterior of the grounded electrode insulator,

'ing the remaining portions of the spark plug. The conical end of shell 2. may be formed ofjsteel, while the electrode 6 may be made of any material, and it will be noted that the exposed portion of the insulator 3 spaces the grounded electrode from the electrode 6.

What I claim is:

1. A spark plug for internal combustion engines comprising a tubeprovided with a hollow downwardly extendmg pointed end, a pointed insulating member located within the tube and extending beyond and below saidhollow pointed end of the tube, and a conductor extending downwardly below the insulator and having a conical lpointed end the length of which is considerably greater than the widest part of the conical end, the surface of which is contiguous with `the surface of the insulator and exposed to the heat of explosion.

2. A spark plug for-internal combustion engines comprising a. tube having an outer .downwardly extending conical surface, a

conductor extending through the tube having a pointed end of greater length than the thickest part thereof projecting downwardly into the cylinder, an insulator interposed between the tube and the conductor and having a portion of the 'surface thereof and the point 7 shall be smooth, and it is apparent that it located between the ltube andthe pointed www@ end of the conductor, said surface of the 1in Jpostiinzionjy whereof aix my signature ilsuator bprodcilg Wit? thefsaild surfao inl 'pi'es'enoe of two Witnesses. ote'tean tesuraceo te ointe" 1 end of the conductor an unbrokenxpdown- `WILLIAM T' M' BESON' 5 wardly pointing conical surface, the onted Witnesses: end of the conductor beingv isolate from.v "R.- H. BLANTAN the tube and the insulator. E. W. LAPSLEY. 

